The present invention relates to a process for producing polyion complexes by reacting a polycation polymer with an inorganic compound in various solvents. Various polyion complexes have been disclosed in the prior art as follows.
1. Polyion complexes prepared by reacting a polystyrenesulfonate with a polyvinylbenzyltrimethyl ammonium salt [Ind. Eng. Chem., 57, (10), 32 (1965)].
2. Polyion complexes prepared by reacting polyglutaminic acid with polylysine [Nihon Kagaku Zasshi 82 (5), 597 (1951)].
3. Polyion complexes prepared by reacting an anionic partial substituent of polyvinyl alcohol with polyvinyl pyridine. (Japanese Unexamined Patent Publication No. 21221/1961).
4. A process for preparing polyion complexes (Japanese Unexamined Patent Publication No. 29830/1963).
5. Polyion complexes of polysaccharide derivatives (Japanese Unexamined Patent Publication No. 59181/1963).
6. Polyelectrolyte complexes derived from polyvinyl alcohol and a process for preparing a film or fiber therefrom (Japanese Unexamined Patent Publication No. 66004/1963).
As is evident from the subject matter of the above references, most of the known polyion complexes are organic-organic polyion complexes. In general, inorganic materials have the advantages of having very good flameproofing properties as well as high dimensional stability, but have the disadvantages of being brittle and having relatively low strength. On the other hand, organic polymers have softness and elasticity and relatively high strength in comparison to inorganic materials. However, the organic polymers have the disadvantages of not having food flameproofing properties and not having good dimensional stability. In order to overcome the disadvantages of both materials with the advantageous features of both materials, it has been proposed to introduce an inorganic material into an organic polymer. In one method of preparing such a material the inorganic material has been introduced into the organic polymer by blending or coprecipitating both components whereby a product is obtained which exhibits improved strength characteristics such as improved tensile strength and an improvement in the decrease of yield elongation. However, the above-described disadvantages of organic and inorganic materials could not be overcome by this technique when the materials were either blended or coprecipitated. When the organic polymer and inorganic materials are blended by the conventional method, it is difficult to uniformly blend the materials and thus an improved preparative technique is required.
A study has therefore been conducted for a method by which an inorganic material can be blended with an organic polymer in a macro-uniform form.